This log file is not mine. It is InBreaker's, but he seems too angry to even bother, so I took the time to bring this up.

A few people have had this problem so far on Spectrum's server, who frequently is at max or near-max WAD count.

Apparently, if the WAD limit somehow gets breached by some new additional file(s) when a player joins a server, it can cause SRB2 to think it has WADs loaded when it doesn't. This can be triggered by adding WAD files prior to joining a server with enough WADs. This can cause crashes and errors.

I spoke to Inu about it (since they were the one who marked it as Won't Fix), and they can't quite remember! The best recollection was that there were TONS of problems with netgame joining with WADs added at the time, and so it was a major issue to handle. Things seem to be a lot better on that front, though, so I've made some headway on that.